Hi, I’m Karl Hoes from the Lincoln Electric Welding School in Cleveland, Ohio. We’re down here in Mooresville, North Carolina at the NASCAR Technical Institute and we’re doing an Advanced Motorsports Seminar. Yesterday, we talked a little bit about identifying or telling the difference between two different filler metals by dropping them on the floor and you can hear one ring and the other one didn’t. One was a 5356 and one was a 4043. Some questions came up as to the difference in these filler metals. Well, the four series filler metal is alloyed with silicone and the five-series filler metal is alloyed with magnesium. Actually, we could use both of these filler metals for most of the jobs we do but we select them from filler metal charts based on strength ductility and really the service conditions of the jobs is very important. A car seat might be made out of 5052 aluminum and we might weld a bracket on made out of 6061, which is alloyed with magnesium and silicon. And we could actually use either one of these filler metals but if I’m looking for strength the 5356 would be stronger and more ductile On the other hand if we’re welding on a radiator, which is also made out of 5052 we’re looking for sustained service temperatures above 150 degrees. 5356 filler metal has too much magnesium for that. It would not be suitable for that application so we select the filler metals based on strength, weldability, service conditions, and actually we have to refer to some filler metal charts to get into that further.